Glad that others agree with me, I wasn't sure if it was a good idea. She is doing so well for a dog over twelve, that I'd like to keep it that way. Sugarcatmom, that was a very good article, interesting to see that 100% of the dogs tested were still immunized at a minimum of 4-5 years, and after seeing the pictures of what can go wrong it definately helps you to decide. I have always given her heartworm tablets, am now wondering if I should keep that up or not. I have to take her in for a heartworm test Friday, I'm curious to see what the vet will say about no distemper shots.